1. Cara Scatena and Allison Schwedock
Lavoisier, Proust and Berthollet and the Laws of Conservation of Matter and Definite Proportions
Cara Scatena and Allison Schwedock

2. Lavoisier Bio: (8/26/1743 [kingdom of france] - 5/8/1749 [paris])
Born into a wealthy family and with the passing of his father inherited a large sum of money
Began his schooling at the Collège des Quatre-Nations 
Studied chemistry, botany, astronomy, and mathematics
Eventually studied uder, Abbé Nicolas Louis de Lacaille, a distinguished mathematician and observational astronomer who lead Lavoisier to his interest in meteorological observation
He established the Law of Conservation of Matter.
Created many theories with combustion

3. Lavoisier
Law of Conservation of Matter- matter can neither be created nor destroyed
Demonstrated that transmutation of water to earth was not possible. 
He discovered that the total mass of the products in a chemical reaction is always the same as the total mass of the starting materials consumed in the reaction
Changed chemistry from qualitive to quantitive 
Oxygen theory of combustion
He burnt phosphorus and sulfur in air, and proved that the products weighed more than the original. Therefore, the weight gained was lost from the air. 
• Methods of Chemical Nomenclature
he invented the system of chemical nomenclature that is still used today, including names such as sulfuric acid, sulfates, and sulfites.

4. Lavoisier
He attempted to take Priestley’s (his rival) credit of discovering that air is composed of two parts, and that one combines with metals to form calxes. 
He also attempting to take Priestley’s credit for discovering that the inflammable air of Cavendish which he called hydrogen, combined with oxygen to produce a dew known as water. 

5. Proust Bio Created Elements from water Law of Definite proportions
(9/26/1754 [angers, france] - 7/5/1826 [paris])
Bio
He was a sickly young child which would eventually interfere with his schooling at Lycée Condorcet
Despite his health fought for the french military for one year
Eventually taught chemistry in France and Spain
Closeted homosexual, whose health deteriorated as he lost family members
Was also an author who published many stories
Created Elements from water
Law of Definite proportions

6. Proust proved this by accurate measurements.
Law of Definite Proportions- states that a chemical compound always contains exactly the same proportion of elements by mass.
proved this by accurate measurements.
showed that cupric carbonate always had 5.3 parts copper to 1 part carbon to 4 parts oxygen.
Created elements from water
His best work (LDP) is derived from controversy with CL Berthollet

7. THE CONTROVERSY
THE LAW OF DEFINITE PROPORTIONS was opposed by other chemists
most notably Proust's fellow Claude Louis Berthollet
who argued that the elements could combine in any proportion.
The existence of this debate demonstrates that, at the time, the distinction between pure chemical compounds and mixtures had not yet been fully developed.
PROUST WAS RIGHT IN THE END!

8. C. L Berthollet
(12/8/1748 [talloire, france] - 11/8/1822 [Arcueil, France])
Bio
Studied at Chambéry and then in Turin where he graduated in medicine.
Had great development in works regarding chemistry making him an active
participant of the Academy of Science in 1780
-- battled with Joseph Proust
⁃ he was wrong and these incorrect solid chemical compounds that do not conform to the law are known as berthollides.
-- member of physics and natural history in Egypt

9. Berthollet
Devised a chemical system of names which serves as the basis of the modern system of naming chemical compounds. 
Carried out research into dyes and bleaches and determined the composition of ammonia.
One of the first chemists to recognize the characteristics of a reverse reaction, and chemical equilibrium.
Potassium chlorate (KClO3), a strong oxidizer, is known as Berthollet's Salt.